Carton structure



Oct. 10, 1950 V A; s. NAPIER 2,525,258

' CARTON- STRUCTURE Filed July 18, 1947 s Sheets-Sheet 1 0a, '10, 1950A. s. NAPIER CARTON STRUCTURE 3 Sheets-Sheet 2 Filed July 18, 1947INVENTO ifiaefiaazi I m Hm Oct. 10, 1950 s. NAPlER 2,525,268

CARTON STRUCTURE Filed July 18, 1947 3 Sheets-Sheet 3 @M MEN PatentedOct. 10, 1950 UNITED STATES PATENT OFFICE 2,525,268 CARTON STRUCTUREArchibald Stuart Napier, St. Paul, Minn.

Application July 18, 1947, Serial No. 761,850

12 Claims.

My invention relates to an improvement incarton and deals moreparticularly with a type of carton which may be locked in open position.

Many types of cartons have been made which are in the form of a trayhaving a base and encircling side walls. In many instances the sidewalls of the tray are locked together in some manner to hold the wallsin fixed relation to the base. Many such locking devices are notparticularly positive in action, thereby allowin the side walls tounfold if strain is place against them. It is important to provide anefiicient lock which will definitely retain the walls in fixed relation.

It is the object of the present invention to provide a carton having abase and side walls foldably connected thereto and in providing a novellocking means at each corner of the carton by means of which the variousside walls may be held in proper fixed relationship. This locking meansis designed to effectively engage flaps on certain of the side Walls tohold the parts in assembled relation.

A feature of the present invention lies in the provision of a cornerlock which is produced by a pair of diverging cut lines extending oneither side of a line of fold and which combine with a pair of foldlines diverging from the first named fold line to the ends of the cutlines. This structure provides a rectangular or diamond shaped areahaving cut lines along two adjoining sides and score or fold lines alongthe remaining two sides. The score line also extends diagonally acrossthe rectangular or diamond shaped area to provide the look.

A feature of the present invention lies in providing a lock which is inthe form of a pair of connected generally triangular portions which maybe bent in unison out of the plane of the panels from which they areformed. When these triangular areas are again folded int substantiallthe plane of the panels from which they are cut, they may overlie a flapor tongue in such a manner as to hold this flap or tongue in fixedrelation to the Walls.

A further feature of the present invention lies in the provision of alock which includes a pair of triangular portions connected along a foldline and cut from the panels on opposite sides of the fold line. Onesuch lock may be provided at each corner of a carton. By folding thetriangular portions out'of alignment with the remainder of the panelsfrom which they are formed, a relatively large opening is exposed in thewalls. A flap or carton portion may be folded to overlie portions of theopenings. By folding the locking means back toward original position theportion of the carton folded to overlie the openings is sandwichedbetween the locking means and the remainder of the wall from which thelocking means is out.

These and other objects and novel features of my invention will be moreclearly and fully set forth in the following specification and claims.

In the drawings forming a part of my specification:

Figure 1 is a diagrammatic view of a blank from which my carton isformed.

Figure 2 is a sectional perspective view of the blank in partiall set upform.

Figure 3 is a view similar to Figure 4 showing the blank completely setup.

Figure 4 is a perspective view of the finished carton.

Figure 5 is a diagrammatic view of a blank showing a modified form ofconstruction.

Figure 6 is a sectional perspective view showing the carton partiallyset up.

Figure 7 is a View similar to Figure 6 showing the carton completely setup. 7

Figure 8 is a perspective Vie of the type of carton shown in Figures 5,6, and 7.

Figure 9 is a diagrammatic view of a blank from which another modifiedform of carton construction may be made.

1 Figure 10 is a sectional perspective View showing the carton partiallyset up.

Figure" 11 is ,a view similar to Figure 10 showing the carton completelyset up.

Figure 12 is a perspective view of the carton of Figures 9, l0, and 11in completely set up form.

The carton A illustrated in Figures 1 through 4 of the drawings includesa bottom panel i0 which is connected along parallelfold lines l l and i2to side wall panels l3 and M respectively. The bottom panel IQ islikewise connected along parallel fold lines l5 .andit to end wallpanels ii and i9 respectively. The end wall ii is connected along a.fold line 2i! to a locking flap 2E. The end wall panel 19 is connectedalong a fold line 22 toa locking flap. 23. j

The side wall [3 is connected at its ends along parallel fold lines. 24'and 25 to" flaps or tabs 26 and 2?. The side Wall M is likewiseconnected along parallel fold lines 29 and 30 to end tabs or flaps 3|and 32 respectively. The fold lines 2-4 and 29 are in substantialalignment with, or a continuation of, the fold line 55. Likewise thefold lines 25 and 3!] are substantially aligned with the fold line l6.

Locking tabs 33 and 34 are provided along the fold lines 24 and 25respectively. Locking tabs and 36 are provided along the fold lines 29and 30 respectively. These locking tabs are shown as generallyrectangular in shape and each of the locking tabs includes a pair ofdiverging cut lines 31 and 39 which come together at an apex along therespective fold line. The cut lines 31 and 39 are preferably of equallength and their ends are joined by score lines or lines of fold 40 and4| which come together at an apex along the fold lines intersecting thelocking tabs.

In other words, each locking tab is similarly formed and comprises apair of rectangular areas of similar size and shape on opposite sides ofa fold line. The locking tab 33 thus includes two similar triangularareas 42 and 43 on opposite sides of the fold line 24. The locking tab34 includes two opposed similar triangular areas 44 and 45 on oppositesides of the fold line 25. The locking tab 35 includes two triangularareas 46 and 47 on opposite sides of the fold line 29. The locking tab36 includes two similar rectangular areas 49 and 50 on opposite sides ofthe fold line 30.

The locking tabs are so spaced and proportioned relative to the lockingflaps 2| and 23 that the flaps 2| and 23 extend substantially to thejunction between the out line 31 and the score lines 46 in foldedposition of the carton. reason for this structure will be more obviousupon an explanation of the manner in which the carton is erected.

In setting up the carton A, the flaps 26, 2'1, 3| and 32 are bentupwardly along their respective fold lines connecting them to the sidewalls l3 and 4. Simultaneously with this action the locking tabs 33, 34,35, and 36 are bent inwardly out of the plane of the remaining portionsof the panels so that the locking tabs are bent inwardly in spout likeform from the walls to which they are attached. The side walls I3 and Mare erected relative to the base panel I0 and the end walls l1 and I9are folded upwardly to lie outwardly of the flaps 26, 21, 3| and 32.

The locking flaps 2| and 23 are then folded over the upper edges of theinwardly bent flaps 26, 21, 3| and 32 to overlie a portion of the innersurface of these flaps. The locking flap 2| lies inwardly of the endflaps 26 and 3| while the locking flap 23 lies inwardly of the flaps 21and 32. The carton is now in the position illustrated in Figure 2 of thedrawings with the locking flaps 2| and 23 partially covering theapertures formed by the inward folding of the various locking tabs.

The next step of the operation is to fold the locking tabs upwardlytoward the plane of the panels from which they are formed. The lockingflaps 2| and 23 prevent the locking tabs from returning completely totheir original form, but these tabs engage inwardly of the locking flaps2| and 23 to hold these flaps in folded position. The triangular areas42 and 46 lie inwardly of the locking flap 2| to hold this locking flapfrom unfolding along the fold line 20. Similarly the triangular areas 45and 50 of the locking tabs 34 and 36 engage inwardly of the locking flap23 holding this flap from unfolding along the fold line 22. In completedform the set up carton A appears as illustrated in Figure 4.

In actual practice two trays such as the tray A may be used intelescoping relation or a cover panel may be attached to one of the sidewalls l3 or I4 to form a top closure for the carton. When once erectedinto the form illustrated in The Figure 4 it is extremely difiicult tointerlock the carton locking means as the locking tabs are extremelyresistant to folding when in the position shown in Figure 4.

By folding the locking tabs inwardly during the folding operation of thecarton no strain is placed upon these locking tabs to place them in thecondition shown in Figure 2. When these tabs are folded from theposition shown in Figure 2 to the position shown in Figure 3, the paperbends somewhat until the two triangular areas are in the same plane.After the two triangular portions of each locking means passes co-planarrelation the bow of the paper snaps the locking tabs into lockedposition. It is extremely difficult to interlock the locking tabswithout tearing the board of which the carton is made.

In Figures 5 through 8 of the drawings I disclose a modified form ofcarton construction which is indicated in general by the letter B. Thecarton B is generally similar to the carton A in form. However, thecarton B has the advantage that the cut lines about the locking tabs arenot visible from the exterior of the carton. The carton B also has theadvantage that the locking tabs may extend the entire height of thewalls of the carton, thus allowing the lock to be employed on a cartonhaving narrow side and end walls.

The carton B includes a bottom panel 5| which is connected alongparallel fold lines 52 and 53 to outer side wall panels 54 and 55respectively. The panels 54 and 55 are connected along parallel foldlines 56 and 51 to side wall liner panels 59 and 60 respectively. Thebottom panel 5| is likewise connected along two opposed ends by foldlines 6| and 62 to end wall panels 63 and 64 respectively. The end walls63 and 64 are connected along parallel fold lines 65 and 66 to lockingflaps or flanges 6'! and 69. A line of fold 10 connects the side wall 54to the end flap 1| and also connects the side wall panel 59 to the endflap 12. The fold line 56 continues between the flaps H and 12 to form afoldable connection therebetween. A line of fold 13 connects the sidewall panel 54 to an end flap 14 and likewise connects the side wallpanel 59 to the end wall flap 15.

A fold line 16 connects the side wall 55 to an end flap 1'! and likewiseconnects the panel 60 to the end fiap 19. A fold line connects the panel55 to the end flap 8| and likewise connects the panel 66 to the end flap82. The fold line 5'! continues between the flap I1 and the flap l9 andbetween the flaps 8| and 82 to form a foldable connection therebetween.The fold lines 10 and 16 are substantially aligned with the fold line 6|while the fold lines 13 and 80 form substantial continuations of thefold line 62.

Locking tabs 83, 84, 85 and 86 are provided in the fold lines 10, 13, 16and 89 respectively. Each locking tab includes a pair of diverging cutlines 81 and 89 which come together at the juncture of the fold lineintersecting the locking tab and the fold lines connecting the innerlining panels 59 and 66 to the outer side wall panels 54 and 55. Thelocking tabs also include diverging score lines of fold lines 96 and 9|which extend from the extremities of the cut lines 81 and B9 to theadjacent ends of the blank at the ends of the fold lines intersectingthe locking tabs.

In other words, the locking tab 83 includes two triangular areas 92and'93 which are oppositely disposed on opposite sides of the fold lines76 and extend the full height of the inner side wall lining panel .59.The locking tab 84 is formed of two rectangular areas .94 and :95 which:are equal in size and shape .andareon opposite sides of the fold line13. The locking tab 85. comprises two similar triangular areas 96 and9.! arranged on opposite sides of the fold line 16. The looking tab 86comprises twos-imilar triangular areas 99 and I99 on opposite sides ofthe fold line 89. These locking tabs are thus similar to the lockingtabs previously described in the carton A, but are different in the factthat the diverging cut lines outlining one-half of each locking tab mayextend to the fold lines 56 and 51 respectively, thus making the lockingtabs the full height of the side walls rather than a smaller fractionthereof. This is permissible in view of the fact that the side wallsand. the connected end flaps .are connected along fold lines so that thecut lines .do

not extend to the edge of the blank.

The manner in which the carton B is set up is very similar to thesetting up process of the car ton A. The side walls are folded so thatthe panel 59 overlies the panel 54 and the panel 69 overlies the panel55. The end flaps on the ends of the side walls may then be bent atright angles to v the side walls, the locking tabs being simultaneouslyforced inwardly to form spout like retaining members as illustrated inFigure 6 of the drawings. The side walls may be erected relative .to thebase panel 5| and the end panels 63 and 69 may be folded upwardly to lieexternally of the end flaps. The locking flanges or flaps 61 and 69 maythen be folded downwardly to overlie portions of the opening formed inthe inner side wall panels and the adjacent end flaps as illustrated inFigure 6 of the drawings. With the locking flanges held in this positionthe locking tabs may be folded upwardly toward their normal coplanarrelation with the panel portions from which they are formed. In thisposition portions of the locking tabs overlie portions of the lockingflaps or flanges as illustrated in Fig ures '7 and 8, thus holding thecarton assembled in the form illustrated in Figure 8.

When in this position the locking tabs .93 and 35 overlie portions ofthe locking flange 61 to retain this flange in folded form, while thelocking tabs 94 and .83 lie inwardly of portions of the locking flange69 to hold this locking flange in folded form.

A modified form of carton C is illustrated in Figures 9 through 12 ofthe drawings. This form of construction has some similarity to thepreviously described constructions in that a similar locking tab meansis used to hold the carton erect. The difference lies entirely in thedetail construction of the flaps connecting the side and end walls.

The carton C includes a base panel I9I connected along parallel foldlines I92 and I93 to side wall panels I94 and I95. The base panel IN islikewise connected along parallel fold lines I96 and I9! to end wallpanels I99 and H9. The end wall panels I99 and H9 are connected alongparallel fold lines III and H2 to locking flaps or flanges H3 and H4.

The end wall panel I99 is connected along a continuation of the foldline I92 to a triangular flap I I5. The rectangular areas betweenthe-side and end walls of the carton are divided into two triangularflaps along a diagonal out line indicated in all instances by thenumeral IIB. One triangular flap'of each corner section is connected tothe adjacent end wall while the other triangular flap of each cornersection is connected to the adjacent sidewall. As previously stated the.flap I5l 5 is connected to the end wall I99 along a continuation of thefold line I92. A similar triangular flap I-I'I is connected along a foldline I I9 to the sidewall I199.

The end wall panel I I 9 is connected to the triangular end flap 129along a continuation of the fold line I92. The triangular flap I.2I isconnected to the side wall I94 along a fold line I22. The flaps I29 andI21 are separated along the cut line I I6.

The end wall I99 is connected to "the triangular flap I23 along acontinuation of the fold line .I 92. A similar triangular flap W4 isconnected to the side wall I95 along a fold line I25. "The end wall H9is connected to the triangular flap I26 along .a continuation of thefold line I93. The triangular flap I2! is connected :to the side wallI95 along a fold line I29.

The end wall flaps H5 and I23 are connected to locking flanges :I 39 andI 3| along continuations of the fold line I II. The end wall flaps I29and I26 are connected to the locking flanges I32 and I33 alongcontinuations of the fold line I I2. The fold lines :I I9 and I are insubstantial alignment with the fold line I96. Similarly the fold linesI22 and I29 are in substantial alignment with the fold line I91.

Locking tabs I34, I35, I36, and I3! are provided in the 'fold linesbetween the side wall panels and the end flaps thereon. Each locking tabis formed by a pair of cut lines I39 and I49 which converge at the lineof fold and by a pair of converging fold lines MI and I42 alsoconverging along the same fold lines. Thus the locking tab I34 is formedof two similar triangular areas I43 and I44 which are connected alongthe fold line H9. The locking tab I is formed of two similar areas I45and I49 connected along the fold line I22. The locking tab I36 is formedof two similar triangular areas I46 and I 49 connected along the foldline I25. The locking tab I3I includes two similar triangular areas I59and I5I connected along the fold line I29.

In erecting the carton C the side walls I94 and I95 are folded upwardlyfrom the base panel I9 I. The end flaps I11, I21, I24, and I21 arefolded inwardly at right angles to the side wall panels and the lockingtabs I34, I35, I36 and I3'I are simultaneously pressed inwardly to forminwardly projecting spout like members as illustrated in Figure 10 ofthe drawings. The end walls I99 and III] are folded upwardly and the endwall flaps thereon are folded to lie externally of por tions of the sidewall \panels. The flaps H5 and I 29 lie outwardly of the side wall I94while the flaps I23 and I26 lie-outwardly of the side wall panel I95.The locking flanges H3 and H9 are folded to lie inwardly of the endflaps on the side wall panels. The locking flanges I39, I3I, I32 and I33of the end wall flaps are folded over the upper edges of the side wallsI94 and I95 to lie iI-Iteriorly of portions thereof. All .of the lockingflanges cooperate in partially covering the openings formed by theinward bending of the locking tabs.

Ihe locking tabs are then folded upwardly into the position shown inFigures 11 and 12 of the drawings, retaining the various locking flangesin place. It 'willlbe seen that each locking tab tends to hold twoseparate locking flanges in locked position. Thus with this cartonstructure, each locking tab engages two locking flanges in place of zoneas in the previously described structures.

Various modifications of my locking tab have been made. In eachinstance, however, the locking tab is formed of two generally triangular[portions on opposite sides of a fold line, two adjacent sides of thetwo triangles being defined by cut lines. If desired portions of thetriangular flaps may be cut away to simplify the folding operation. Forexample the apex of the two fold lines forming each locking tab could becut away so as to prevent bulging of the stock at these convergingfolds. However, in such an event the operation of my device is similar.

In accordance with the patent statutes, I have described the principlesof construction and operation of my carton construction and while I haveendeavored to set forth the best embodiments thereof, I desire to haveit understood that obvious changes may be made within the scope of thefollowing claims without departing from the spirit of my invention.

I claim:

1. A carton lock for connecting a panel to a (pair of panels connectedalong a fold line, the lock comprising a pair of similar generallytriangular sections on opposite sides of the fold line, said triangularsections being defined by diverging cut lines meeting at the fold line,and a pair of fold lines extending from the outer ends of cut lines tothe first named fold line, said lock being engageable against the firstnamed panel when this first named panel is interposed between 'at leastone of the triangular sections and the panel from which this section iscut.

2. A lock for locking carton panels together, the lock including alocking tab formed in a pair of panels connected along a fo d line, thelocking tab including a pair of connected diverging cut lines forming anapex at the fold line, and a pair of fold lines extending from the outerextremities of the cut lines and forming an apex at the first named foldline, said locking tab being foldable into or out of the planes of thepanels when said pane s are folded into angular relationship, saidlocking tab being engageable with a looking panel engaged between aportion of the locking tab and the panel from which the locking tabportion is formed.

3. A carton corner lock including a pairof panels foldably connectedalong a fold line and a lock formed in said panes a locking tab formedin said panels, said locking tab including a pair of connected cut linesforming an apex at the fold line and diverging therefrom, and a pair offold lines extending from the ends of the cut lines and convergingtoward the first named fold line, said locking tab being foldable intoor out of the plane of the two panes when the panels are folded intoangular relationship.

4. A carton construction including a base panel, side and end wallsextending upwardly from said base panel, end flaps on the ends of saidside walls foldable into parallel adjacent relation to said end panels,a corner lock in said side walls and said end flaps, said locksincluding a pair of diverging cut lines connected at the fold linebetween said side walls and said end flaps, and a pair of fold linesextending from said out lines toward said fold lines, and a lockingflange on said end walls engageable between portions of said locks andsaid end flaps.

5. A carton construction including a base panel, a series of side wallpanels extending upwardly therefrom, certain of said side wall panelsbeing connected along a vertical fold line to a flap lying in surfacecontact to an adjacent side wall, a locking tab at the juncture betweensaid iii) certain side wall and said flap, said locking tab including apair of cut lines connected at said fold line and diverging therefrom,and a pair of fold lines extending from the ends of said out lines tosaid first named fold line, and a locking flange on the overlapping sidewall extending between said locking tab and said flap.

6. A carton including a base panel, rectangularly arranged side wallpanels thereupon extending upwardly therefrom, a flap on one of saidside walls overlying the next adjacent side wall, a locking tabintersecting the line of fold between said one side panel and said flap,said locking tab including a pair of substantially triangular areasarranged on opposite sides of said fold line and being defined by twoout lines connected at an apex at the line of fold and a pair ofconvering lines of fold extending from the inner ends of said out linestoward the line of fold, and a locking flap on the wall overlapped, saidlocking flap being folded over the first named flap and engaged betweenthe locking tongue and the remainder of the flap.

'7. A carton including a base panel, side wall panels foldably securedthereto and extending upwardly therefrom, two opposed side wall panelshaving flaps thereon folded inwardly of the intermediate panel, lockingtabs formed at the juncture between said side walls and said flaps, saidlocking tabs comprising a pair of connected cut lines connected at saidfold line and diverging therefrom, and a pair of converging fold linesextending from said out lines toward said first named fold line, and alocking flange on the side wall overlapped extending between portions ofsaid locking tabs and the remainder of said flaps.

8. A carton including a base panel, rectangularly arranged side wallpanels extending upwardly therefrom, two opposed side Wall panels havingend flaps thereupon connected thereto along vertical lines of fold, saidend flaps being foldable inwardly of the intermediate side wall, alocking flange on said intermediate side wall folded over the upperedges of said flaps and lying inwardly of portions of said flaps, andlooking tabs holding said anchoring flap in place, said locking tabsincluding similar triangular areas on opposite sides of the line of foldconnecting the opposed side walls to said end flaps, said similartriangular area being defined by a common base at the fold line, twodiverging connected cut lines, and two converging fold lines from saidout lines to said line of fold, said anchoring flange being positionedbetween portions of said locking tabs and the remainder of said endflaps.

9. A carton including a base panel, side wall panels extendingupwardlytherefrom, side wall liner panels foldably connected to the upper edgesof said side wall panels and foldable into parallel surface contacttherewith, end flaps on said side wall liner panels foldable intoangular relation with said side wall panels, end wall panels foldablyconnected to said base panel and extending upwardly therefrom outwardlyof said end flaps, and a locking flange on the edge of said end wallsfoldable over the end flaps of said side panels to lie inwardly thereof,and locking tabs engaged outwardly of said locking flange to hold saidlocking flange in folded form, said looking tabs including a pair ofdiverging cut lines connected at the lines of fold connecting said linerpanels to said end flaps, and converging lines of; fold connecting theouter ends of said cut line to said lines of fold between said linerpanels and said end flaps.

10. A carton .blank including a bottom panel, side wall panels connectedthereto along parallel fold lines, end wall panels connected to saidbase panel along parallel fold lines, end flaps connected to said sidewall panels along parallel fold lines, locking flanges connected to saidend wall panels along parallel fold lines, and locking tabs formed atthe juncture between said side wall panels and said end flaps, eachlocking tab including a pair of diverging cut lines connected at thelast named fold lines, and lines of fold extending from said out linesand converging toward said last named fold lines.

11. A carton blank including a base panel, side wall panels foldablyconnected thereto along parallel fold lines, side wall liner panelsfoldably connected to said side wall panels along parallel fold lines,end wall panels connected to said base panel along parallel fold linesintersecting said first named fold lines, said intersecting fold linesextending through said side wall panels and side v wall liner panels toconnect these last named panels with end flaps, locking tabs in saidintersecting fold lines between said liner panels and said end flapsconnected thereto, said locking tabs including cut lines diverging fromsaid intersecting fold lines and connected at said intersecting foldlines, and converging score lines extending from said out lines to saidintersecting fold lines, and locking flanges foldably connected to saidend Wall panels along parallel fold lines.

12. A carton including a base panel, side Wall panels foldably connectedthereto along intersecting fold lines, end Wall panels foldablyconnected to said base panel along lines of fold intersecting said firstnamed fold lines, said intersecting fold lines and said first named foldlines continuing through said side walls and end walls to connect all ofsaid walls to end flaps, locking tabs at the intersection between saidintersecting fold lines between said side Walls and the end flapsconnected thereto, each locking tab including a pair of diverging cutlines connected at said intersecting fold lines, and converging scorelines extending from said out lines to said intersecting fold lines, andlocking flanges foldably connected tosaid end Walls and the end flapsconnected thereto along parallel fold lines.

ARCHIBALD STUART NAPIER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Halladay May 30, 1933

